Tuesday, February 2, 2016

At the Cellular Level.

Irrelevant Intro Begins Here. To skip this part, please scroll down to the next bit of red text, found 5 paragraphs below.

I've started my blog entries off with so many different versions of "It's been a long time since the last time" that I'm having trouble coming up with a new phrase that doesn't sound like a broken record. A broken record. Record. And if that's not enough, now I've gone a step further and started this "here's a bunch of writing you'll probably want to skip." The absurdity that I'm doing exactly this same thing yet again is not lost on me. I appreciate your concern.

I need to convey the same old tired sentiment that I always say, but it has to sound innovative and sexy. Because that's the high standard to which we've become accustomed. Alas, the only expertise from which I can draw inspiration seems to be that offered by those mythological beasts we collectively know as "candidates." And though I'm desperate, I can't allow myself to be conflated into that social clique.

If I were, I might still be able to live with myself. But my reputation would suffer because you, dear reader, would instantly think less of me. On a personal level, that's okay. But now that I have the shop open and I'm playing adult games and stuff, I have to act like other people's personal opinions actually carry some weight in my corner of this vast universe. And if I'm wrong about all of that, then I'm wrong about my own opinion that lovers of Old Things Volvo are people of a high enough caliber that they aren't dulled to the point of apathy by this every-four-year-election-circus. We notice things. We think critically. This is not an endorsement of any candidate nor an invitation for political debate. Comments are moderated.

See what I did there? Paid you a subliminal compliment in order to foster a positive assessment and silently bolster my standing.

Now that we're all thinking about how much we don't like at least one of the someones who is working to become the leader of the free world and our moods have most certainly risen to something between Giddy With Excitement and Pure Bliss (no need to thank me), let's get back to the car thing.

The shop is legit: we got the stickers to prove it.


Irrelevant Intro Ends Here.

One of the things about this car that I've never wanted anyone to know (Hi Mom! Hi Dad! Hi Beloved Wife!) is that it's been limping along on a crummy old original fuel tank for a few years. This isn't so bad, exactly, except that the pickup tube (you Volvo folks already know where this is headed) rusted and became perforated. The pickup tube is a metal straw that enters the tank near the top, and pokes down toward the bottom. Just like your soda straw does when you're sipping on a cola.

Anyway when these tubes get holes in them, they can't draw fuel from the bottom of the tank, and you end up basically running out of gas even though you might have several gallons sloshing around in there. With this one, I could fill the tank to its astonishing 9 gallon capacity, and after using about 3 gallons, the car would coast to the side of the road. For a long distance endurance kind of car, a range of 50 miles per tank is unsuitable. Eventually, 3 gallons became less than 2, and I was managing about 30 miles between fillups. I was not popular with gas station attendants (we don't pump our own here in Oregon) who, after being asked to "fill 'er up!" barely got things started when it was already over with.

There's an analogy in there somewhere, but I just can't find it.


See the shiny spots? That's where raw gas ends up.

I will not disclose the method by which a faulty fuel pickup tube was circumvented. Either you shouldn't know, or you already do.

There were also some pinholes in the top of the tank that allowed small amounts of raw gasoline to exit the top of the tank and stink up the whole car. We thought about what we need from our replacement tank.

It had to be bigger than the original, needed a provision for a fuel gauge sending unit, had to have a rollover valve, and had (this part is obvious) to fit into the trunk along with a lot of other things. Though a proper FIA certified fuel cell (that's bonafide race car stuff) is a really smart thing, it's also a thousand dollar plus kind of thing. For the events we're looking into, the cell need not be FIA certified.

So there was a lot of thinking about capacity and dimensions and how other stuff would stow in the trunk. Do we want a tall skinny fuel cell? A low flat one? How important is the filler placement? Sump or no sump? We finally settled on a 17 gallon piece that would tuck nicely* into the floor, included a fuel gauge sending unit, and had its filler located pretty close to the original fuel filler hole in the left rear fender. I don't know if we'll use the original fuel filler hole, but that seems more likely if the tank filler isn't on the opposite corner of the trunk.

*tuck nicely: 1. stow neatly within a small enclosed space in an aesthetically pleasing and functional manner. 2. the garish - but appropriately concealed - result of angle grinders, hacksaws, welders and various other devices of irreversible alteration applied to an otherwise perfect foundation with the robust intention of accommodating the absurd.


One of these is the old tank. The other is the new one.
The new tank is pretty flat, so it won't take up a lot of trunk space. If this were a track car, the cell would drop down into a recess ('the cell sits in the well') and we'd have a lower center of gravity (good thing) as well as more available trunk space (irrelevant on the track). But for this car, we really don't want a box of gasoline acting like low hanging fruit out underneath the car's stern. And this way, we can drop the original tank right back into place if we want; or we can quickly put a proper race cell in place should the opportunity arise.


Fuel tank hole gets bigger. Hard to tell with all the crap on the floor under there.
Another round of Irreversible Changes That Get Me Hate Mail, and the 59 year old Swedish sheetmetal trunk floor is adjusted to accommodate the new feedbag.

Adding a flange to the newly cut side.


Doesn't have to be pretty. Luckily.
One super-important aspect was the fuel sending unit. There are a few different kinds, none of which is advertised as having the proper resistance range to match the 444's original fuel gauge. This is no surprise. So we ordered the "GM" sending unit, then bought a gauge that would communicate with that. Then we spent a LOT of time figuring out how to fit an aftermarket VDO fuel gauge into the original instrument panel. Because that's how we want it.

The idea was to use sheet steel (right) and then...
... drill a hole for the gauge.
The issues with this: only one 2 inch gauge will fit on either side of the speedometer. And fitting one gauge per side requires irreversible mods to the instrument housing. The trick is to recess the gauge such that it's behind the lovely chrome fascia, but not all the way in the back of the housing where you can't see it. Thus, the plate shown above.

Because I practice full disclosure: if you've read my prior blog entries already, you know that I'm not always ever very any good about getting X to completion before starting in on Y. One result of this is that I sometimes do things that turn out to be completely worthless less valuable than I might choose. Another result is that I have a big stash of cool stuff to use when I make other cool stuff someday. All that fiddling with the new gauge and making up a panel fits into both of these categories. Because here's the thing I never could have predicted: not only is the mounting plate for the GM sending unit the exact same diameter as the Volvo piece, it also has 5 mounting holes like the Volvo piece. And though the holes aren't equally spaced from one another on the GM part, the unequal spacing is identical to the unequal spacing on the Volvo part.

In short, the two sending unit mounting provisions are identical. The Volvo sending unit fits perfectly. This wonderful news has delightfully rendered many hours of fettling irrelevant. Woot.


GM, top. Original Volvo, bottom.
The other happy coincidence is that because we chose a fuel cell that's about the same height as the original tank, the only thing we had to do to make the sending unit float span from the very bottom of the tank to the very top was bend the arm a little. In the Volvo tank, the sending unit mount is recessed (this keeps it tucked nicely* below any cargo that would be stowed in the trunk). Because it's recessed, the float actually reaches higher than the mounting plate when indicating 'full.' This new tank isn't like that, so the float reach doesn't need to go as high - by about a half inch. It does need to reach lower than before, though. By about a half an inch. Maybe this coincidence isn't any big deal, but I'm pretty stoked. Wouldn't have been possible with any other fuel cell that I was considering. A quick test with the ohmmeter tells us that we're good to go.

*See prior reference. Or ibid. I don't know.

Empty.

Full.
I'm really pleased that we'll be able to use the original fuel gauge. And because we can do that, I've decided to not install a new VDO temp gauge and to run with the original. We aren't using the original oil pressure gauge nor the ammeter. It might seem like a minor thing, but despite evidence to the contrary, we want this car to stay old. We're changing it for a specific purpose and many of these changes call for modern elements. But these bits of modernization are side effects resulting from a primary goal that relates to vintage authenticity.

That's the Volvo sending unit on the right.
 Because the tank isn't secured the same way as the original, we added a ground wire to the sending unit cover. That's a simple thing.


There are a few things to keep in mind if you install a cell, even if it's a Not-Actual-Race variety like this one. Ensure that it's adequately supported from below, for example. And there's a vent, which you'll want to connect to a fuel-compatible line and then route well above the filler level before fitting it somewhere outside the trunk (and also outside the passenger compartment) so that it can draw clean air into the tank as the fuel level drops. Our vent tube leads up, then loops around and comes back down with the open end hiding behind the license plate and fitted with a small filter to keep the big chunks of dirt out.




And that's it for now. There's less trunk space than before, but there's enough. For comparison, here's a 544 that's run La Carrera 8 or 10 times and hasn't run out of gas:

That's 22 gallons of awesome, plus the spare/jack/tool kit, fire extinguisher and first aid kit. Photo courtesy of Michael Sharp.
We've done a few other things along the way that are kind of cool (and maybe a little silly) but they're minor and not worthy of their own blog post. So we'll just add them here.

First: based on advice from LCP veterans, the car now has windshield squirters:


That's the bottle. Keen eyed readers will notice that the coil and Crane box have been moved.
... and some exterior hinges that allow the trunk to open all the way:

The hinge pins are held in place with hitch pin clips so that we can remove the trunk lid altogether in about 20 seconds without tools. The original latch stays locked so you won't steal it.

And that's about it. We're looking forward to taking the car up to the Swedish Car Day event at the XXX Drive In up in Issaqua (that's sort of near Seattle) on Feb 14th. Hope to see you there!

'til next time -